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Open source search tools
Use the search tools below to find open access articles
No cost academic search engines for published papers and preprints - Comprehensive
Bielefeld University’s Academic Search Engine (BASE)
BASE is one of the world's most voluminous search engines especially for academic web resources. BASE provides more than 240 million documents from more than 8,000 content providers. You can access the full texts of about 60% of the indexed documents for free (Open Access). BASE is operated by Bielefeld University Library.
CORE’s mission is to aggregate all open access research outputs from repositories and journals worldwide and make them available to the public. In this way CORE facilitates free unrestricted access to research for all.
Directory of Open Access Journals
The DOAJ (Directory of Open Access Journals) was launched in 2003 with 300 open access journals. Today, this independent database contains over 15 000 peer-reviewed open access journals covering all areas of science, technology, medicine, social sciences, arts and humanities. Open access journals from all countries and in all languages are welcome to apply for inclusion.
Comprehensive, indexes academic information from various online web resources especially useful when used with one of the browser plugins such as Unpaywall
Microsoft Academic Research
Use with one of browser extensions Such as Unpaywal. Microsoft Academic understands the meaning of words, it doesn’t just match keywords to content. For example, when you type “Microsoft,” it knows you mean the institution, and shows you publications authored by researchers affiliated with Microsoft. Similarly, Microsoft Academic knows journal titles, conference names, and many research topics. Try these queries to understand the power of semantic search and unleash it yourself!
OSF PrePrints (Center for Open Science)
In academic publishing, a preprint is a version of a scholarly or scientific paper that precedes formal peer review and publication in a peer-reviewed scholarly or scientific journal. The preprint may be available, often as a non-typeset version available free, before and/or after a paper is published in a journal.2,288,043 searchable as of November 25, 2020
ScienceOpen is a discovery platform with interactive features for scholars to enhance their research in the open, make an impact, and receive credit for it. We provide context building services for publishers, to bring researchers closer to the content than ever before. Our advanced search and discovery functions, combined with post-publication peer review, recommendation, social sharing, and collection-building features make
Semantic Scholar (Allen Institute)
A Free, AI-powered Tool for Navigating the Scientific Literature Search over 180 million papers across all fields of science
A social networking website for researchers. Contains more than 100 million publication pages.
The Multidisciplinary Preprint Platform
A platform dedicated to making early versions of research outputs available, including original research articles and reviews
Specialty Open Access Platforms
Bioline International is a not-for-profit scholarly publishing cooperative committed to providing open access to quality research journals published in developing countries. BI's goal of reducing the South to North knowledge gap is crucial to a global understanding of health (tropical medicine, infectious diseases, epidemiology, emerging new diseases), biodiversity, the environment, conservation and international development. By providing a platform for the distribution of peer-reviewed journals (currently from Bangladesh, Brazil, Chile, China, Colombia, Egypt, Ghana, India, Iran, Kenya, Malaysia, Nigeria, Tanzania, Turkey, Uganda and Venezuela), BI helps to reduce the global knowledge divide by making bioscience information generated in these countries available to the international research community world-wide.
BioOne was established in 1999 in Washington, DC, as a 501(c)(3) not-for-profit organization by five scholarly collaborators: the American Institute of Biological Sciences, the Scholarly Publishing and Academic Resources Coalition (SPARC), The University of Kansas, Greater Western Library Alliance, and Allen Press.
CERN Document Server
Over 650,000 bibliographic records, including 320,000 fulltext documents, of interest to people working in particle physics and related areas. Covers preprints, articles, books, journals, photographs, and much more.
arXiv is a free distribution service and an open-access archive for 1,799,152 scholarly articles in the fields of physics, mathematics, computer science, quantitative biology, quantitative finance, statistics, electrical engineering and systems science, and economics. Materials on this site are not peer-reviewed by arXiv.
Educational Resources Information Center (ERIC)
The ERIC Selection Policy establishes the standards and criteria for selecting materials for inclusion in the ERIC collection. It states broad collection goals and defines the standards and criteria required of approved sources and individual materials in the ERIC digital library. The purpose of the selection policy is to provide consistency in the approach for reviewing and selecting sources and individual items, and clearly communicate policy and process to staff, users, publishers, and individual submitter of material.
Mendeley is a free reference manager and academic social network that can help you organize your research, collaborate with others online, and discover the latest research:
Organic Eprints is an international open access archive for papers and projects related to research in organic food and farming. The archive contains full-text papers in electronic form together with bibliographic information, abstracts and other metadata. It also offers information on organisations, projects and facilities in the context of organic farming research.
Penn State’s CiteSeerX
CiteSeerx is an evolving scientific literature digital library and search engine that has focused primarily on the literature in computer and information science. CiteSeerx aims to improve the dissemination of scientific literature and to provide improvements in functionality, usability, availability, cost, comprehensiveness, efficiency, and timeliness in the access of scientific and scholarly knowledge. Rather than creating just another digital library, CiteSeerx attempts to provide resources such as algorithms, data, metadata, services, techniques, and software that can be used to promote other digital libraries. CiteSeerx has developed new methods and algorithms to index PostScript and PDF research articles on the Web.
PubMed is a free search engine accessing primarily the MEDLINE database of references and abstracts on life sciences and biomedical topics. The United States National Library of Medicine at the National Institutes of Health maintain the database as part of the Entrez system of information retrieval.
SSRN, formerly known as Social Science Research Network
s a repository for preprints devoted to the rapid dissemination of scholarly research in the social sciences and humanities and more. Elsevier bought SSRN from Social Science Electronic Publishing Inc. in May 2016
U.S. government’s Science.gov
Science.gov searches over 60 databases and over 2,200 scientific websites to provide users with access to more than 200 million pages of authoritative federal science information including research and development results.
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